1. Field of the Invention
The invention relates to a field-effect-controllable semiconductor component, including a semiconductor body with the following features:
a) an inner zone of a first conductivity type, which adjoins a first surface of the semiconductor body, PA0 b) an anode zone of an opposite, second conductivity type, which adjoins the inner zone in the direction of the first surface and which adjoins the second surface in an opposite direction, PA0 c) at least one first base zone of the second conductivity type, which is embedded in the first surface in the semiconductor body, PA0 d) at least one source zone of the first conductivity type, which is embedded in the first surface in the semiconductor body, PA0 e) at least one source electrode, which makes contact with the base zones and the source zones, and PA0 f) at least one gate electrode, which is insulated from the semiconductor body and the source electrode by a gate oxide and which at least partly covers parts of the first base zones appearing at the first surface.
A semiconductor component of the above-described type is known as an IGBT (Isolated Gate Bipolar Transistor) and is described, for example, in the journal "Electronik" Electronics! 9, 1987, pages 120 to 124.
Furthermore, IGBTs with trench structures derived from DRAM technology are known. The difference between those IGBTs and the IGBTs mentioned above resides in the fact that the gate electrode is produced as a V-shaped or U-shaped trench through the use of anisotropic etching (etching in the direction of the crystal grating), in such a way that the gate electrode made of doped polysilicon or metal is disposed in an insulated manner on silicon dioxide. Very low surface resistances and high packing densities are achieved in that way. The nonplanar configuration of the structure and the sharp deviation from the production technology used in integrated circuits is also disadvantageous. On the other hand, as is known, the respective turn-on resistance R.sub.ON and forward voltage V.sub.SAT of an IGBT in trench technology can be reduced with respect to the IGBTs mentioned at the outset, as a result of the fact that parasitic JFETs, which exist between the cells of planar transistor structures, are in principle dispensed with.
Advantageously, in the case of IGBTs, the inlet point of the electrons and the holes are physically separated. That can be achieved, for example in SOI technology (Silicon-On-Insulator), through the use of a buried silicon dioxide layer.